code: def test_merge_preserve_geodataframe():
      # https://github.com/geopandas/geopandas/issues/2932
      ser = GeoSeries.from_xy([1], [1])
      df = GeoDataFrame({"geo": ser})
      res = df.merge(df, left_index=True, right_index=True)
      assert_obj_no_active_geo_col(res, GeoDataFrame, geo_colname=None)
      expected = GeoDataFrame({"geo_x": ser, "geo_y": ser})
      assert_geodataframe_equal(expected, res)
  
imports: import pandas
  import pyproj
  import pytest
  from shapely.geometry import Point
  import numpy
  from geopandas import GeoDataFrame, GeoSeries
  from geopandas.testing import assert_geodataframe_equal
label_desc: Use image node_id 22 for calling a global function with example usage: test_merge_preserve_geodataframe() without return types